The head of the World Health Organization gave a strident defence of his agency’s handling of the coronavirus pandemic on Wednesday, in response to U.S. President Donald Trump’s criticism and suggestions that Washington could review its funding for the agency, Reuters reports.

WHO Director General Tedros Adhanom Ghebreyesus called for unity and a halt to “politicization” of the global health crisis, specifically urging China and the United States to show “honest leadership”.

Tedros said he expected U.S. funding to continue with traditional bipartisan support.

Trump and his administration repeated its criticism, on Wednesday. Secretary of State Mike Pompeo said Washington was re-evaluating U.S. funding to the body, saying international organizations utilizing U.S. taxpayer money needed to deliver on their goals. But he objected to a leadership change at the WHO at this time.

U.S. contributions to the WHO in 2019 exceeded US$400 million, almost double the second-largest country donor, according to U.S. figures. The WHO website shows the United States as its top donor, contributing nearly 15 percent of the budget.

Trump told the daily White House briefing on the coronavirus that Beijing’s payment was a small fraction of Washington’s WHO contribution, and that was “not fair at all.”

“So, we’re going to do study, investigation. And we’re going to make a determination as to what we’re doing. In the meantime, we’re holding back. We ... want to see.”

Trump said the WHO issued a statement on January 14 saying “there was no human-to-human transmission” and criticized him “very strongly” when he said he was going to shut down flights from China.

Tedros said the WHO had “kept the world informed about the latest data, information and evidence” and noted that Thursday would mark 100 days since China first notified the organization of cases of “pneumonia with unknown cause” on December 31.

Tedros, a former foreign minister of Ethiopia, rejected Trump’s suggestion that the WHO was “China-centric,” saying: “We are close to every nation, we are color-blind.”

Earlier, Dr Bruce Aylward, senior adviser to Tedros, also defended the U.N. agency’s relationship with China, saying its work with Beijing authorities was important to understand the outbreak.

“It was absolutely critical in the early part of this outbreak to have full access to everything possible, to get on the ground and work with the Chinese to understand this,” said Aylward, who led a WHO expert mission to China in February.

WHO Director General Tedros Adhanom Ghebreyesus has been heavily criticized for the slow reaction to the coronavirus outbreak in China's Wuhan in December.

WHO chief rejects 'politicization' of pandemic, tells US and China to show honest leadership